Tape-transmitter



D. MURRAY.

TAPE TRANSMITTER. APPLICATION FVILED AUG. 14, 1914.

2 $HEETSSHEET l- Patented Dec. 27, 1921.

.IIIIV/InI/I i f werJ ian M 0. MURRAY.

TAPE TRANSMITTER. APPLICATION FILED AUG. 14, 1914.

Patented Dec.27, 1921.

2,SHEETSSHEET 2- fnvenzbr;

Donald JWdrT-a,

names stares PATENT @FFHQK DONALD MURRAY, OF LONDON, ENGLAND, ASSIGNORTO THE WESTERN UNION TELEGRAPH COMPANY, A CORPORATION OF NEW YORK.

TAPE-TRANSMITTER.

Application filed August 14, 1914. Serial No. 856,845.

To all whom it may concern:

Be it known that I, DONALD MURRAY, a subject of the King of GreatBritain and- Ireland, and residing at 19 Victoria Mansions, Queens. ClubGardens, London, IV, England, have invented certain new and use.- fulImprovements in and Relating to T ape Transmitters, of which thefollowing is a specification.

This invention relates to an improved perforated paper tape automatictransmitter for use with a keyboard tape perforator in a multiplexprinting telegraph system. The chief objects of the invention are toreduce as much as possible the delay between the perforation and thetransmission ofthe messages and to provide for automatic starting andstopping of the transmitter under the control of thetension of theperforated paper tape.

' In the accompanying drawings Figure 1 is a plan View of thetransmitter. Fig. 2 is a sectional elevation along the lines A B in Fig.1.

Figs. 3 and dare details.

Fig. 5 is a side elevation partly in section along the lines C D, Fig.1, and E F, Fig. 2.

Fig. 6 is a sectional elevation along-the line Ur I-I, Fig. 1.

Fig. 7 is a modification of part of Fig. 2.

Fig. 8 is a diagrammatic sketch of the automatic starting and stoppingmechanism of the transmitter.

Fig. 9 is a detail of Fig. 7.

Fig. 10 is a plan View of the modification shown in Fig. 7.

Fig.11 is a detail of part of Fig. 7.

Fig. 12 is analternative arrangement of the automatic starting andstopping mechanism.

- Fig. 13 shows a piece of the perforated paper tape.

In connection with the multiplex printing telegraph system for which thetransmitter described in this application is specially adapted, I havealso designed a key-board tape perforator for preparing telegraphmessages in the form of perforated paper tape, one of the chief objectsof that machine being to have the least possible delay betweenperforation of the tape and transmission of the signals by means oftheperforated tape. For this purpose the work of perforation takes place atthe extreme lefthand side of the key-board perforator. The

Specification of Letters Patent. I Patgnted feed holes 6, Fig. 13. Byhavin Dec. 27, 1921.

eXtremeleft-hand end of this key-board perforator is shown in dottedoutline at 1, Figs.

The telegraph tape transmitter, which is the subject of the presentpatent application is designed to work in conjunction with the key-boardperforator, and it is arranged with the same object, namely, to reduceto the minimum possible amount the delay between the preparation and thetransmission of telegraph messages. The mechanism of transmission in thetransmitter is therefore arranged to work at the extreme right-hand sideof the instrument. Transmission takes place at the point where the hooks4, Fig. 2, engage with the holes in the paper tape 5. The transmitter isso designed that it will work conveniently at a distance of about oneinch and it may even be worked at a distance of half an inch from theleft-hand side of the key-board perforator. The tape produced by thekey-board perforator has the letter groups of perforations arrangedacross the tape, as shown in Fig. 13, and the letter perforations areinch (2.54 m/m.) apart on the tape lengthwise, each letter correspondingto one of the row of the perforator punching the message hides in thetape at the extreme left-hand side of the machine, and the transmittertransmitting on its extreme right-hand sidewith so little -space betweenthe two machines, the number of letters on the tape 5, Figs. 1 and 2,between the point. of perforation and the point of transmission can bereduced if de sired to as little as 12. As the speed of transmission onthe Murraymultiplex printing telegraph, for which this transmitter isspecially suited, is about 40 words per minute on each arm or channel ofthe cir-' cuit, the delay between perforation and transmission is inthis way reduced to about three seconds. In other words, transmissioncan take place up to within 12 letters or three seconds of the lastletter punched on the key-board perforaton- This is a much greaterreduction of delay than has ever before been. achieved in thetransmisvers 8, pivoted at 11, Fig. 2, being pushed.

mechanism that will automatically stop transmission when the transmitterhas caught up to within, say, 12 letters of the perforator. Thetransmitter is arranged to run at a uniform speed of about 40 words perminute (four letters per second), and if the transmitter followed closeup to the perforating machine, the key-board operator would be underanxiety lest the transmitter should overtake the key-board perforatorand break the tape. He would have to be always watching the transmitterand this watching would distract his attention from his proper work ofperforating the messages. It is still more convenient for the operatorif the transmitter is not only self-stopping but also self-starting. Asfar as I am aware, no mechanism of .this kind has been devised before Idevised it"for a multiplex printing telegraph perforated tapetransmitter. The conditions to be satisfied are rather complicated. In amultiplex printing telegraph, transmission on each arm or channel of thecircuit takes place 'at fixed intervals, in the Murray multiplex aboutevery quarter of a second. An electric impulse from the distributer,known as the cadence, operates successively the transmitter on eachchannel. In the Murray multiplex tape transmitter, which forms thesubject of the present application, the cadence impulse from the distributer energizes the magnet 7, Figs. 1 and 5, which feeds the papertape forward one letter space and sets a row of five contact levers 8,Figs. 1, 2'and 5, into a particular group of positive and negativecontacts representing a letter signahthe contact leover against thepositive contacts in the bar 9, or against the negative contacts in thebar 10., Immediately afterward the rota- -tion of the contact brushes ofthe dis- 1 tributer sweeps this group of signals into the telegraphline, the two operations of settin theft-contact levers and sending thesigna intofthe line being repeated regularly every quarter second. It isobvious that the starting or stopping of the transmitter must take placebetween the transmission .ofthe signals. .If the transmitter was stoppedin the 'middle of the transmission of a signal into the telegraph line,one of two things would happen. 'Either (a) the group of positive andnegative contacts inthe transmitter representing a letter would remainundis turbed, or (b) the group would be broken up and the contact leversthrown back on to the negative contact bar 10, or onto the positivecontact bar 9.. In the former case the same letter would be sentrepeatedly, once every quarter second, into {the telegraph line, therebycausing an error in the printed message at the distant station throughthe continued repetition of the same letter. In

the latter case, the contact levers all being attracted and released.

by the armature spring 14,

tact levers 8 will catch thrown over to the negative or the positivecontact bar in the midst of'the transmission of the signal group intothe line, the signal would'necessarily be mutilated and a wrong letterwould be printed at the distant station. It is therefore necessary thatthe starting and stopping mechanism shall operate between thetransmission of signals. Another condition is that when the machinestops, the, contact levers must be thrown over onto the negative contactbar 10, so that only negative current flows 'to line. If positivecurrent went to the line from the transmitter while the transmitter wasstopped it would cause the printer to keep on operating. Anothercondition that is desirable, though not to fill, if the transmitter isto be selfstarting as well as self-stopping, is that the transmittermust-not be continually starting and stopping; This would cause needlesswear on the starting and stopping mechanism with risk of error throughthe continual chatter of starting and stopping. It is desirable to havea period of several'letters intervening between stopping and starting,about six to-twelve letters (three seconds) forming a convenientinterval. These conditions are fulfilled in the following way:

Transmission does not begin in the transabsolutely necessary,

and 5, of the transmitter magnet 7 has'been 75 is the backstop for thearmature. The transmitter can therefore be stopped or started safely atthe instant when the magnet 7 has attracted its armature 12. At thispoint the attraction I of'the armature, by mechanism to be describedpresently, causes the paper feeding and contact selecting mechanism torise to the pointfor starting work, and at the same time the rising of asmall loop or stirrup 13, Figs. 2 and 4,'throws over the contact levers8 rom their last letter permutation on to the negative contact bar 10readyto be set,

into the next permutation as soon as the mac;

net 7 releases its armature 12, the tape feeding and the contactsetting'being performed Figs. 5 and 6, on the back stroke of thearmature. Consequently if the armature 12 is caught by suitable"mechanism when attracted by the magnet 7 and retained in that positionthe congo over and remain on the negatlve contact bar 10. Negativecurrent only will go into the telegraph line, and n'egatl've' currentproduces no effect on the printer at the distant station. .l/Vhen it isdesired to stop the transmitter, a pawl 15, F 1g. 6, pivoted at 16, isallowed to fall and moment when the armature is attracted to 5126 asteel bar prolongation 17 of the arma- 'pawl 15 .has its hook slightlyundercut 18,.

Fig. 6, so as to engage with a similar undercut portion of the steel bar17, forming a prolongation of the armature. Thisrundercut portionprevents the pawl being raised except'when the armature .is attracted bycurrent in the magnet. The slight amount of motion permitted to thearmature is just 7 sufiicient to free the pawl and allowit to be raised.The armature stopping pawl can therefore only be raised or lowered whenthe armature is attracted by the magnet. As the transmitter is stoppedwhen the arma ture is'held close to the magnet, the starting andstopping of the transmitter at the right moment- 15 provided for by thisspecial form of pawl and armature. An L shaped lever 19, pivoted at 20,hereinafter described as the tape lever, is arranged with the end 21free to rise or fall in the space where the paper tape passes from theperforator to the transmitter. (See Figs. 1 and 2.) The tape forms aloop 5 at this point, rising up out of the perforator and passing downinto the transmitter. The tape lever, pressed up by a coiled spring 22,igs. 1 and 5, rises in side ofth s paper loop. As the tape graduallypasses into the transmitter, if perforating stops, the loop becomessmaller and the tape lever is gradually depressed. The armature stoppingpawl 15 is pivoted'at 16 on the frame of the transmitter below thetapelever, and the two are connected to ether by a small spiral wirespring 23, Figs. 6 and 8. In order that this spring may not have to bestrong with consequent heavyaction, it is desirable to make the armaturestopping pawl 15 ofbrass or other non-magnetic metal, the holding tipbeing reinforced with a small piece of clockspring steel 24, Fig. 6. Asteel paw is liable to be attracted and held down on the magnetarmature. As

i the tape lever 19 rises the stopping pawl 15 tends to rise, and as thetape lever falls the stopping pawl also falls, being assisted in thisrespect by a separate spring of its own, 25, tending to pressit down inantagonism to the spring connecting it to the tape lever. The pawl istherefore balanced between two opposing springs and when free rises orfalls with the rise or fall of the tape lever. When the tape lever isdepressed by the paper tape until all the loose tape in the loop haspassed into the transmitter, as

at 5, Fig. 2, the armature stopping pawl' 15. has been allowed to falluntil its hookrests on theedge of the prolongation of the armature 17.The moment the armature is attracted the pawl drops over the edge andthe armature is caught and the pawl is locked by hooking into theundercut portion of the" extension bar of the armature (see 18, Fig. 6).If six or eight letters are now perforated on the key-board perforatorso as to give a little slack tape, as shown by the dotted outline 26,Fig. 2, the tape lever 19 rises and puts lifting tension onthe armaturestopping pawl 15 by means of the spiral spring 23 connecting the two. Assoon as the cadence impulse attracts thearmature,

that is to say, at the right moment for starting the pawl is freed andjumps up under the tension of the spring.' The transmitter then startsworkin until the loose tape is again used up. For reasons alreadyexplained it is not desirable to have this starting and stopping actionrepeated every one or two letters. This can be avoided by ha 1- ing thespring 23 connecting the tape lever and the stopping pawl of suitablestrength and extensibility. A short stiff spring will start and stop onone or two letters. The lighter and more extensible the spring withinreason the greater the number .of letters that will intervene betweenstarting and stopping.

Fig. 8 shows the automatic starting and stopping mechanism indiagrammatic form. The reference numbers enable the action to be easilyfollowed from the description already given. 7 is a small portion of thetransmitter magnet attracting the armature (or steel bar extension) ,soas to release or catch the pawl at the right moment.

When it is desired to stop the transmitter by handand prevent itstarting again, the operator depresses the tape lever 19 by hand andlooks it down with a small lever latch (not shown). To start thetransmitter it is only necessary to throw off the latch so as to freethetape lever. It will be seen that the essence of the automaticstarting and stopping of the transmitter just described is catching andretaining the armature of the magnet in the attracted position.Obviously, in place of the mechanical arrangem'ent just described, it ispossible to arrive at the same resultby keeping the circuit ofthe magnet7 closed. This can be i The three magnets are operated by the batat theright moment. ,At the same time the tery 67. 66 is the spindle of themultiplex distributer and 64 is the revolving contact brush which, atregular intervals, closes the circuit by making contact with the segment65. While the transmitter is running, mag- I nets 62 and 63 attract 68and 69 at regular so that the short circuit is closed from the battery67 ,through the magnet 62, wire 73,

lever 19, contact 71, lever 68, wire (4, transmitter magnet 7 and backtothe battery 67. This holds the transmitter magnet 7 closed tape loop haspulled lever 19 down so that it is caigght by-the pawl 70. Thetransmitter,

there ore, cannot start again until the right moment, that is, when thetape loop is again increased in size so as to leave the tape lever 19free to. rise. This happens at-the right moment because the pawl 70 hasnot been retracted to release 19 until the magnet 63 is en'ergizedat thesame time as the transmitter magnet.

. The transmitter itself is composed of a series of five verticalcontact levers 8 arranged. side by side in a row between two contactbars 9 and 10, one connected to positive and the other to negativebattery.

The contact bars carry 'adjustable contact screws 27 of the usual type.Projecting horizontally to the left from each of the vertical contactlevers from their hearing point there is an arm 28, Fig. 2, carrying aglass-hard steel wedge 29, on its end; A series of five flatsteelsprings 30' with sharp ends bent to the right press against the steelwedges, thereby causing the contact levers to press firmly against thepositive or the negative contacts.-- There is a'corresponding arm 31,

Fig. 2, projecting from each of the five con tact' 'jlevers to theright, To each of these right-hand armsthere is attached-a spring 32carrying a small block of fiber or other a suitable insulating material33. Raising or lowering these little insulation blocks about i gth inch(about 1.5 mm.) will throw the contact levers on to the negative or thepositive contacts. On the right of the vertical; contact levers andabove'the right-hand projecting arms, there is an oscillating frame 34,Figs. 2,3 and 4, carrying a group of six small levers 35, pivoted attheir centers 36 on the free end of the oscillatingframe. Theoscillating frame 34 and the hook levers 35 are shown in detail in Figs.3 and '4. The frame34 is pinned to the shaft 37, Fig. 5,

. 6. The lever 38 is connected to the steel bar extension 17 of thearmature of the magnet 7 by the steel rod 39 with rounded ends, one ofwhich fits into a socket in the lever 38 and the other 'end into asocket in the bar 17. The spring 14 pulls the lever 38 in the directionof the arrow 40. The armature, through its bar 17 when the magnet isenergized, pushes the lever 38 in the direction of the a row 41. In thisway the shaft 37 is oscillated back and forward. The shaft 37 thereforerocks the frame 34, Fig. 2, so that the hook levers 35 pivoted at 36rise and fall about g-th inch (about 3.2 mm.). In Fig. 3, a plan view,the frame 34 is pinned to the shaft 37 and has two arms, 42 and 43. Atthe free end there is a small spindle 36 upon which the hook levers35'are hung. In Fig. 4 a front elevation, it will be seen that inaddition to the hook levers there is a loop or stirrup 13. It is thisstirrup 13 that lifts the small blocks 33, Fig. 2, thereby thr0wingthecontact levers on to the negative con 'tacts when the magnet isenergized so as to attract its armature and causing the frame 34 to riseand with it the hook levers 35 and the stirrup 13.

The upper end of each of the levers 35 carries a hook or claw 4 adaptedto engage in the perforations in the paper tape. The lower ends of theselevers project downward just clear of the insulation blocks of thecontact levers." If there .is a perforation in the paper tape thecorresponding claw falls into it and thelower end of the lever carryingthe claw 'n'ioves'inward under the tension of spring 44so as to beimmediately over the insulation block 33 of the corresponding contacglever. The oscillating frame rises and falls regularly about th inch(3.2 mm.-)= asthe result of the operation of thev transmitter magnetworking from the cadence contact of the distributer.

When the framefalls the claws engaged in the perforations in the papertape drag the tape down th inch (2.5 mm.) and at thesame time the lowerends of the claw levers whose claws have entered perforations in thetape strike the insulation blocks and ,throwthe corresponding contactlevers over on to the positive contacts. The other hook levers, meetingno hole in the tape, are held out so that they donot strike the blocks33.

In this way a particular letter permutation of five positive andnegative-contacts is set X up and the distributer of the multiplexsystem sweeps the signal into the telegraph line. The next moment thetransmitter magnet is energized and it raises the free end'of theoscillating frame about lth inch only' central feed holes,

4 ing them (3.2 mm.). in the paper and rise a'little over th inch (2.54mm.) soas to engage positively in the next letter group of perforationsacross the tape; A small friction block 45 prevents the paper tape fromrising as the claws rise. It also serves as a guide for the hook levers.The result is that the claws keep clawing the tape down letter by letterand at the same time setting? the contact levers in various positive andnegative permutations in accordance with the'perfo'rations in the papertape. It has been mentioned that there are six claws or hooks. Fiveoperate on message holes, and the sixth engages in the row of feedholes. The sixth claw lever 46, Fig. 4, is cut short below so as not toaffect any contact lever.. The object of the sixth claw lever is to feedthe tape through the transmitter at points where there are and also torelieve the paper of the strain of being fed forward by one claw only.This would tend to tear the perforations. The sixth lever is made withadouble claw, so that there are never less than two holes in the tapeengaged by claws and usually. three or four. A lever 47 is arranged atthe back of the transmitter to throw the claws out from engagement withthe paper tape when it is desiredto remove the tape from thetransmitter.

An alternative method of feeding the tape and setting the contact levercombinations is shown in Figs. 7, 9, 10 and 11. In this case thelVheatstone method of feeding the tape forward by a star-wheel 48 isemployed. The oscillating frame in this case consists of a single arm 34pinned to the oscillating shaft 37. At the free end the arm 34 carries asmall spindle and friction roller 49. This extends in front of the fivelevers 50. These levers are pivoted at 51 and are pressed against 49 bythe five springs 52.

At their upper end the five levers 5O carry five needles 53, which passthrough holes in the paper tape and enter the holes in the steel plate54. These needles correspond to the needles of thelVheatstonetransmitter. When the lever 34 rises, the spindle and roller 49 press upagainst the inclined or bent portion of the levers 50, thereby throwbackso that the needles are withdrawn from the paper tape. As the lever 34continues to rise the pawl55, attached to the lever 34, rises and movesthe ratchet wheel 56, Fig. 11, around one tooth and it is a space.

caught by the retaining pawl 57 The ratchet 56 is on the same smallspindle 58, Fig. 10, as the star-wheel 48. The paper tape is in this wayfed forward one letter The levers 50, when thrown back by the lever 34rising throw the contact levers 8 over on to the contact bar 9 by meansof five flat springs 58 engagingin slots in in The claws slip out of theholes.

, needle 53.

sulation blocks 59 fastened in the arms 31 of the the contact levers '8.In this case the contactblock 9 is negative and 10 is positive.

When the lever 34' falls, the levers 50, acti'ng'under the control oftheir springs 52, press their needles 53 against the paper 'tape. Ifthere are message holes in the tape,

the corresponding needles enter the holes and their levers 50 moveforward and thereby throw their contact levers 8 over on to the positivecontact' bar 10. In positions where there are no holesin the tape thecor? responding needles cannot enter andthe corresponding leyers 8remain on the negative contact 9. Suitable arrangements are made forreleasing the tape either by moving out the steel plate 54, Fig. 7 or bycarrying the star-wheel and ratchet-wheel on an oscillate ing frame thatcan be moved back so as to liberate the paper tape. Fig. 9 shows theupper part of one of the levers 50 and its The automatic starting andstopping action already described is exactly the same in the case ofthis arrangement as in the case of the hook or claw lever arrangement..It will be seen that in this case also and wedges 29, Fig. 2. Insteadof this jockey spring arrangement, the levers 8, Fig. 7, may each bebalanced between two spiral springs, one of these spiral springsconnecting each lever 8 to each of the levers 50. In this case 58 and 59are omitted. If any lever 50 moves to the right as itspin 53 enters ahole in the tape, the spring connecting it to lever 8 pulls lever 8 overon to contact 9 against the, tension of the opposing spring, spring-52of the corresponding lever 50 being sufficiently strong for thispurpose. This balanced spring arrangement is the same in principleas'that shown in Fig. 8, though usedfor an entirely different purpose.In this case the pawl 15 (Fig.8) repin the drawings,- and may pass tothe floor through a hole in the table or along under the transmiter tothe left. The tape when freed fromthe claws or-the pins and.

star-wheel, can be removed from thetransn iitter instantly bywithdrawing it sidewise. h

e machine is provided with a cover 60, Fig.5, which may be, lifted offwhen 'required.

It will be understood that, in the foregoing description, where I havespoken of positive currents and negative currents, and have spoken ofnegative currents as producing no effect on the printer at the distantstation, these terms positive and negative are purely relative. .Thereverse. arrangement is equally practical. Ordinarily, the printer atthe distant end is so' arranged that a signal consistin of negativeimpulses only produces no e ect on that printer. But, of course, it ispossible to arrange the printer so that signals consisting of negativeimpulses only do produce an effect on that printer, while signalsconsisting of positive impulses only produce no effect on the printer.In such case, usually, the contact member 10 of the'transmitter will becon-- nected to a source of supply of positive cur-.

rent, and the contact member 9 will be conne'cted to'a source of supplyof negative cur- 'rent. 7 In the specification, the terms pos1t1ve andnegative have been used merely forconstep by step type,

tape for automatically stopping the transtradistinction and forclearness and simplicity of language.

Having now described my invention, what I claim as new and desire tosecure by Let ters Patent is:-'

1. In an automatic tape transmitter of the step by step type, meansoperated by the tape for stopplng thetransmitter automaticombinations ofcally, means for sendin difierential impulses suc as posltive andnegative or make and break impulses together with means for sending apredeten. mined combination of impulses continuously to line when thetransmitter is stopped automatically by the tape, scribed.

2. In an automatic tape transmitter of the means operated by the mitterbetween signals, together with means for sending a predeterminedcombination of impulses when the transmitter is stopped,

substantially as described.

3. In an automatic tape transmitter, means for sending signals, meansoperated by the tape for starting the transmission of signals,together'with means for sending currents of one direction onlyto lineWhenth'e transmitter is stopped, substantially as described.

4. In an automatic tape transmitter, means for sending signals, meansoperated by the tension of the tape for starting the transmitterautomatically, together with "means for sending a predeterminedcombination of impulses to the line when the transmitter is stopped,substantially as described.

5 In an automatic tape transmitter, means.

substantially as de- 7 for sending signals, tape for starting andstopping the transmitter automatically,

together with means for sending a predetermined combination of impulsesto the line when the transmitter is stopped, substantially as described.

6. In an automatic'tape transmitter, means for sending" signals, meansoperated by the tension of the tape for starting and stopping thetransmitter automatically, together with means for sending apredetermined combination of impulses to the line when the transmeansoperated by themitter is stopped, substantially as described.

7. In an automatic tape transmitter, means for'perforating said tape,means for transmitting signals corresponding to the perforations on saidtape, a lever actuated I acting'mechanically with said armature forretaining or releasing said armature to stop and start-the transmissionof signals automatically, substantially as described.

8. In an automatic tape transmitter,

means for perforating said tape, means for transmitting signalscorresponding to the perforations on said tape, a lever actuated.

by the length of tape between the perforator and transmitterpanelectromagnet adapted to be intermittently energized in the transmissionofsignals, an armature co-acting with said electromagnet, a locking-pawl adapted to engage the said armature in the energized position ofsaid magnet, together with a resilient "connection between Said lockingpawl and said lever, substantially as described.

9. In an automatic tape transmitter, means for perforating said tape, anelectro* magnet, means for energizing said electromagnet, a frame, aplurality of'hook' members in said frame, said electromagnet forreciprocating said frame, and causing said hook members to engage withthe perforations in said tape, a plurality of contactmembers, meansco-acting with the hook members which engage with the perforations tooperate the corre sponding contact members oh ;one stroke of said frame,means for returning said contact membersto their initial'position on theother stroke of said frame, together with means controlled by a lengthof tape for stopping or starting the reciprocations of said frame,substantially as described.

10. In an automatic tape transmitter,

means for perforating tape, an electromagnet, means for intermittentlyenergizing said electromagnet, a frameaa plurality of means co-actingwith i ing said frame and causing certain ofsaid hook members to engagewith the perforations in said tape a plurality of contact members, meansco-acting with the hook members which engage with the perforations tooperate corresponding contact members on one stroke of said frame, meansfor returnin said contact members to their initial position on the'otherstroke of said a pivoted contact arm arranged to move from one to theother, of perforated-tape controlled means comprising a finger and apivoted support therefor,-and elastic pres- .sure meanstending to causesuch finger to engage perforations of the tape when such perforationsare opposite said finger, and means for moving said finger back andforth, said movable contact arm having a sure means tending to causesuch finger to.

spring portion which is in the path of movement of the finger when thelatter is in engagement with a perforation of the tape, and which is outof the path of movement of such finger when the latter is not inengagement with a perforation of the tape.

12. In an impulse transmitter, the combination with opposed contactmembers, and a pivoted contact arm arranged to move from one to theother, of perforated-tape controlled means comprising a finger and .apivoted support therefor, and elastic pressure means tending to causesuch finger to engage perforations of the tape when such perforationsare opposite said finger, and means for moving said finger back andforth, said movablecontact arm having a portion which isin the path ofmovement of the finger when the latter is in engagement with'aperforation of the tape, and which is out of the path of movement ofsuch finger when the latter is not in engagement with a perforation ofthe tape, and restoring means for said contact arm comprising meanscarried by the finger-support and arranged to engage and restore saidcontact arm upon return movement of said support.-

13; In an impulse transmitter, the combination with opposed contactmembers, and

a pivoted contact arm arranged to move from one to the other, ofperforated-tape controlled means comprising a finger and a pivotedsupport therefor, and elastic presengage perforations of the tapewhen-much perforations are opposite said finger, and means for movmgsaid finger back and. forth, said movable centaetnarm having a portionwhich is in the path of movement of the finger when the latter is inengagement with a perforation of the tape,-and which is out of the pathof movement of such finger when the latter is not in engagement with aperforation of the tape, and a loop depending from said finger supportto beneath the contact arm and arranged to engage and restore saidcontact arm upon return movementof the finger support.

14. In an impulse transmitter, the combination with opposed contactmembers and a movable contact arm, adapted to engage one side or theother of said contact members at will, and a case inclosing said contactmembers and contact arm, of a rock shaft projecting from the outside'ofthe case thereinto', means carried thereby for moving said contact arm,a magnet and an armature therefor, both external to the case, and meansfor communicating motion from said armature to said rock shaft.

15. In an impulse transmitter, the combination with opposed'contactmembers and a movable contact arm, adapted to engage one orthe other ofsaid contact members at will, and a case 'inclosing said contact.

members and contact arm, of avrock shaft projecting from the outside ofthe case thereinto, means carried thereby for moving said contact arm, amagnet and an armature therefor, both external to the case, and meansfor communicating motion from sald armature to saidrock shaft,comprising a of the tape and arranged 'to lock said armaturein attractedposition when the tape becomes too taut. v

17 In an impulse transmitter, the combination with tape-controlledcontact means, and operating means therefor, comprisin a magnet and anarmature therefor, an means operatedby said armature for operating saidcontact means, of mechanical armature-locking means controlled by thetension of the tape and arranged to lock said armature in attractedposition when the tape becomes too taut, and-to release said armaturewhen the tape slackens from such taut condition.

18. In an impulse transmitter, the combination with tape-controlledcontact means, and operating means therefor, and means operated by saidarmature for operating said contact means, of a detent arranged binationwith tape-controlled contact means,

andoperating means therefor, comprising a magnet and an armaturetherefor, andmeans operated, by said armature for op-' erating saidcontact means, said'a-rmature having a hook-shaped locking portion, of adetent, arranged to move into position for engagement with saidhook-shaped locking portion when said armature is in attracted osition,and when in such position to permit slight freedom of movement of thearmature, said detent having a hook which engages with the said hoolcofthe armature'when the latter retracts slightly.

20. In an impulse transmitter, the combination with tape-controlledcontact means, and operating means therefor, comprising a magnet and anarmature therefor,an'dmeans operated by said armature for operating saidcontact means, said armature having a hook-shaped portion, of a detentwhich, in the vicinity ofsaid armature, is

' of non-magnetic material, said. detent hav-' inga hard projectinghook-shaped portion, said detent arranged to move its hookshaped portioninto position for engagement with the hook-shaped armature portion whensaid armature is in attracted posi- -tittn, and when in such position topermit slight freedom. ofmovem'ent of the armature, but not sufficientmovement of said armature to cause operation of the contact means.

21. In, an impulse transmitter, the combination with tape-controlledcontact means,

and operating means therefor, comprising a magnet and an armaturetherefor, and

' means operated by said armature for operating said] contact means, ofa sprin actuated armature-locklng means, contro means, operated by thetension of the tape, and a spring connection-between said control meansand armature-locking means, said armature locking means. beingbalanced'between said spring connection and the actuating spring of sucharmature locking means.

22. The combination with a tape perfora-j tor arranged to deliverperforated tape in a substantially vertical direction, of an impulsetransmitter arranged to receive such tape in an approximately vertical.direc-' tion opposite that of delivery of the tape from the perforator,said transmitter being located in close proximity to said perforator,whereby a tape loop is formed between the perforator and thetransmitter, said transmitterhaving feed means arranged to cause motionof the tape into the transmitter in substantially the direction ofdelivery of that tgpe the transmitter.

23. The combination with a tape perforator arranged todeliver perforatedtape in a. substantially vertical dlrection, of an im-- pulsetransmitter arranged to receive such tape in an approximately verticaldirection oppositethat of delivery of the tape from the perforator, saidtransmitter being located in close proximity to said perforator, wherebya tape loop is formed between the perforator and the transmitter,saidtransmitter havingfeed means arranged to cause motion of the tapeinto the transmitter in substantially the direction of delivery of thattape to the transmitter, and control means for said transmittercomprising a movable'control member adapted for acting upon the tapeloop so formed between the perforator and the transmitter, and tendingto maintain that loop, said control means arranged to be actuated bytightening of the tape loop and consequent motion of the control member.

In testimony whereof I have aflixed my signature in presence of-twowitnesses.

' DONALD MURRAY. Witnesses:

P. A. OUTHWAITE,

H. D. J AMESON.

